The development and refinement of wireless communication services and devices continues to occur at an extremely rapid pace. One problem associated with wireless communication devices relates to determining a physical location of a device. It can be highly desirable to locate a wireless communication device for a variety of purposes, such as when there is reason to believe that a subscriber associated with the device is experiencing an emergency situation, or when the device has been misplaced. Position location is also desired in applications such as personnel and asset tracking, information services, gas/food/lodging locations services, and entertainment. A solution to such problem must be carefully considered within cost, size, and power consumption limitations of wireless communication systems and devices.
When an individual calls 911, for emergency assistance, the call is typically passed along by a telecommunications carrier to a local Public Safety Answering Point (PSAP), which is responsible for dispatching police, fire and medical services. For a caller from a landline telephone, the PSAP can precisely identify the caller's location and telephone number even if the caller does not know his or her location. However, there is a dilemma when the caller is a wireless telephone user.
Today, wireless subscribers make a significant number of emergency calls. The PSAPs, however, are unable to pinpoint the location of these callers. Many wireless networks do not provide the PSAP with Automatic Number Identification (ANI) or Automatic Location Identification (ALI). Without the caller's ANI and ALI, the PSAPs have no means for re-establishing contact with these callers or identifying the location of the caller. This is important in case the call is cut off and cannot be reestablished by the caller, or for the PSAP to establish the nearest appropriate emergency facility to send. Furthermore, in the United States, the Federal Communications Commission (FCC) is requiring mobile communications operators to detect the position of a cellular telephone calling 911.
However, on a mobile phone or terminal, there is generally one portion of the phone that is desirable for GPS antenna placement. In a talk position, the desirable antenna placement for GPS is in a same area as that of the mobile phone's dual band antenna. A problem is that the close proximity of the GPS antenna to the dual band antenna means that any noise or spur from the dual band antenna, falling in the GPS band, may severely desensitize the GPS receiver. This can lead to non-compliance with the FCC directive, e.g., the inability to acquire and process GPS signals—such is the case even if the GPS and dual band antennas perform well independently.
In addition to position location, mobile phone service providers are building out infrastructure to provide much more than just voice functionality to mobile handsets. Higher data rates and multiple frequency bands for GSM, PCS, 802.11 and Bluetooth are needed to allow interactive game playing, near-real time streaming video, audio downloads of music and even formation of ad-hoc networks with other nearby users or devices. This presents an additional problem of adding another antenna to the mobile phone or terminal.
One solution to the aforementioned problems is to situate the internal antennas at different locations in the mobile phone or terminal. However, in such situation, at least some of the antennas will not be at an optimal location, as they might be covered by the user's hand. Another solution is to switch off a Code Division Multiple Access (CDMA) module's transmitter during Global Positioning System (GPS) operation. However, this is also undesirable, as the modules are not able to function at the same time. Accordingly, an improved system or methodology for antenna configuration is desired.